Known pronunciation errors in the TTS

vakt is pronounced wrong when said separately. En vakt sounds right, but if you just listen to the word vakt itself, it's said wrong. https://www.duolingo.com/comment/6873143 (vakt should always be pronounced with a short a)

33 Comments

Thanks for compiling this list, Arnauti! Some are a mystery to me (det=dom in this one case), and some are understandable (kör and kör are two different words, and we haven't had any luck in finding a TTS that can say "read" and "read" correctly either). It is hard to find a perfect voice, but this one makes fewer mistakes than the previous one, huh? =]

It's much, much better than the previous one. eller liknande for el isn't good, but the other one said - out loud as bindestreck, so… The new one only has rare errors on less common words, whereas the old one made mistakes on some very common ones. I think especially de and bakom were unforgivable errors of the old voice.
And thank you vivisaurus for helping us get this new voice in place!

PS I didn't compile the list all on my own, we've been doing it together in the internal wiki.

The answer is probably "not in the current system", but I wonder how possible it would be to mark these problem words somehow and replace their sentence recordings with sound files from a different TTS program?

I like the idea. But even if that is possible, I doubt its feasibility as a long-term solution. TTS systems tend to generate the speech on-the-fly (with caching to prevent unnecessary calculations), meaning that virtually any word can change when an update is applied to the system. And it may well be that the word is pronounced correctly when used in conjunction with other words (not including the el error here), since the correct pronounciation by necessity depends on syntactic analysis as well as prosodic information, both of which have to be derived contextually.

Huh. Somehow, I'd assumed DL would pregenerate all sentences in their courses and just pull each file up when necessary. But I suppose there's nothing wrong with your method, either. It would save on storage, not to mention being more easily extensible to add new sentences.

Thanks for commenting. Is the text input reparsed, or double parsed in any way? The det -> dom case would make sense if the det was converted into de in any way, either through text shortening or because det is pronounced de - which is itself pronounced dom.

Neither reason sounds particularly plausible, and the Occam explanation would be that it's simply an odd mistake. Just throwing it out there. All in all, a major improvement if you ask me. :)

So they did reply back to me, and my message with a link to this thread has been forwarded to the developers behind the Astrid voice. I don't know how often they released updates though, nor how long it will take Duolingo do install any updates.

That's interesting! It could be a problem with words like "kör", "banan" and "planet" though, since the faulty pronunciations actually exist but mean something else.

The old voice had the right pronunciation for choir (kör) but not for drive (kör) and for the new one it's the other way around. I guess it's complicated to make the computer voice able to choose the right one for both cases.

A lot of the errors can be fixed by marking up the text passed to the Ivona engine. I don't know how much integration work the Duolingo people have done, but it should be possible to fix most of the errors above by providing hints to the TTS.